Authorities tightened security at Rio Hondo High School following an alleged threat to shoot up the school.
Rio Hondo Superintendent Ismael Garcia said the campus was put under shelter in place status around 1 p.m. Thursday.
Garcia said a shelter in place is a security measure one step below a lockdown.
School officials closed all doors while police performed a perimeter search.
Superintendent Garcia told Action 4 News that a student received a cell phone call where the caller said he was going to shoot up the school.
The student notified a teacher who notified administrators.
Superintendent Garcia said the school district takes all such calls seriously and enacted the extra security measures, which only last about 40 minutes.
Only students from band and athletes using the open gym were reportedly on campus at the time of the incident.
No injuries were reported during the incident while investigation into who made the phone call continues.